Electroplating equipment



July 5, 1932. KIRCHNER 1,865,767

ELECTROPLATING EQUIPMENT Filed Dec. 6, 1950 TTORNEY Patented July 5,1932 UNITED STATES PATENT; OFFICE MARTIN KIRCHNER, OF BERLIN-LANKWITZ,GERMANY, ASSIGNOR TO UNITED CHRO- MIUM, INCORPORATED, 01' NEW YORK, N.Y., A. CORPORATION OF DELAWARE mornormrme nouirmr Application filedDecember 6; 1980, Serial No. 500,459, and in Germany October 18, 1929.

10 porting the articles in the bath in conjunction with means forshaking, oscillating or vibrating the tray continuously. A considerablesaving of time is thus attained by my improved apparatus as the time forintroducing the articles into the machine is shortened,

as comparedv with known equipment, since the articles in bulk can simplybe poured on to the plate or into the tray or trough. My improvedapparatus also retains the advantage of the continuous motion of thearticles and thus leads to the production of very uniform coatings in acomparatively short time. I

My improved apparatus is particularly suitable for producing coatings ordeposits of chrome, nickel or zinc on base metals, since thedifiiculties arising in the production ofsuch coatings in otherapparatus are effectively avoided. If the objects to be treated 30 arenot to be suspended in the bath individualficulti'es are entirelyeliminated by my im 1y, which requires much time and is thus veryexpensive, the electroplating would have to be carried out in tumblersor oscillating ap paratus immersed in the electroplating solution.

In such apparatus frequent although short interruptions in thedepositing process occur on some of the objectsso that dull and brittlecoatings or layers are produced. These dif- "proved apparatus.

In a; preferred form of my apparatus two diflerently acting groups ofdriving memhere are connected to the tray or trough. This takes place insuch a way that one group of driving members engaging the tray at one,{end shakes, vibrates oroscillates the tray continuously, while theother group of driving members engaging the tray at the opposite endraises this end of the tray intermittently articles, such as into one orthe other of two'limit positions. In consequence of the cooperation ofthese two groups of driving membersthe. sup

porting tray, which has alwaysa f'slight 'incllnation, one end or theother being in .a raised position, the objects move alternately from oneend of the tray to the other due, to the shaking or vibrating action,whereupon after some time the far end of the tray is moved into theother limit position and the objects travel in the opposite direction.This construction may be further improved. While in the just describedembodiment of my invention two separate driving elements are required asubstantial simplification is brought about by another feature of .myinvention accord'ng to which; a single device is provided or operatingthe tray carrying the objects to be plated. The tray is here movablysuspended from rods and these rods are limited in their oscillatorymotion by encountering stationary stops. When the rods come in contactwith these stops at a certain speed they are suddenly arrested with ashock and the articles resting upon the perforated tray are thrownforward upon the ray.

Two embodiments of my invention are illustrated in the drawing afiixedto my specification and forming part thereof. The drawing shows:

Fig. 1, a perspective view of one embodiment, and

Fig. 2, a sectional elevation of. the other embodiment.

Referring to Fig. 1 of the drawing l indicates a tank containing theelectroplating solution in which, for instance, a plate shaped anode 2is suspended. As cathode serves a sieve-like perforated plate 3 withraised edge 4, tray or trough. One end 5 of the plate 3 is connected toa lever 7 pivoted or fixed at 6 to which is hinged a connecting rod 9continuously driven by an eccentrlc- 8.

The plate 3 is connected as the cathode. For

this urpose the lever 7 maybe provided with an electrieallywellconducting core or wire enveloped by an insulating material. Thiscore'is connected to the negative pole of a source of current. Ifpreferred the lever 7 may consist of an elastic material and then berigidly fixed at the point 6. In this case the passage of the current atthe point 6 takes placebetween stationary parts. V

The other end 10 of the tray 3 is connected to arod 11 eccentricallysecured to a disk 12 driven by a clockwork mechanism in customary andtherefore not shown manner. On the drivin shaft 13 of this disk 12 is 10mounted a further disk 14 on which there are fixed twodiametrically-opposite pins 15. In the position shown the lower pin 15is in contact'with the armature 16 of an electromagnet 17 so that therotation of the shaft 13 and 15 thus a motion of the tray 3 by the lastdescribed operation gear is prevented. If the circuit of theelectromagnet 17 is broken, for instance at the contact 18, the armature16 of the electromagnet drops off and thus releases the shaft 13. Theopening of the contact 18 takes place periodically during such shortperiods that during the next following completion of the circuit of theelectromagnet 17 the shaft 13 is again arrested due to Y the pin 15shown at the top in the drawing coming in contact with the armature 16of the electromagnet 17.

The apparatus functions in the following manner: The objects in bulk tobe electroplated are poured on to the tray 3, the raised edge or rim 4preventing the articles from dropping off. The current and the drivingmechanism for the tray 3 are then switched on. Owing to"the continuousvaction of the eccentric gear-8, 9 the tray 3 with the articles upon itis continuously shaken, vibrated or oscillated. Since, as shown in thedrawing, the tray or plate 3 is slightly inclined the objects restingupon it move towards the opposite end 10 of the tray under the action ofthe shaking or oscillatory motion. After some time the shaft 13 isreleased in consequence of the disengagement of the locking arrangement15, 16 and the eccentric gear 11,

12 raises the end 10 of the tray which up to now occupied the lowerlimit position into the upper limit position. The articles on the traynow move towards the end 5 of the tray under the action of the shakingmotion imparted to the tray by the eccentric gear 8, 9. This procedureis repeated until the articles have a coating or layer of the desiredthickiiess. Preferably the tray is lifted out of the bath together withthe finished articles and immersed again after the finished $1 ticleshave been removed and the fresh raw articles placed upon it.

To facilitate the introduction and the removal of the goods theconnection between the rod 11 and the disk12as well as the connectionbetween the rod 7 and the lever 9 and the attachment at 6 may be madedetachable satbat after detaching these connections the plate 3 with thearticles may be lifted out of the bath by means of the rods 7 and 11. If

7 desired a pair of rods like the single rods 7 and 10 may be providedwhereby a tippingover of the tray 3 during the electroplating process orwhen lifting the tray out of the bath is effectively avoided.

Referring to Fig. 2 of the drawing the sieve-like tray or trough withperforated bottom 25 connected as cathode is movably suspended in thetank 22 containing the electroplating solution 21, by means of the rods23 and 24 pivoted at 26 and 27 respectively. The objects to be platedare again placed on this sieve. The rods 23 and 24 are adapted tooscillate or vibrate around the stationary spindles 28 and 29. The driveof the sieve is effected by means of the wheel 30 rotatin continuouslyand on the face of which is pivoted the connecting rod 31 hinged to thesliding bar 32.

The bar 32 is passed through an eye 33 in the rod 23 and coupled to thisrod by means of the springs 34 and 35. To stop the vibrating oroscillating motion of the rods suddenly stops 36 and 37 are provided.

These stops are preferably made adjustable to enable the shocks whenarresting the rods to be controlled and to be made stronger or Weakeraccording to the size and shape of the articles to be plated. Thisobject, viz. the adaptation of the apparatus to various objects, mayalso be attained by providing a plurality of plates or trays withperforations of different sizes.

The anode 38 is by the aid of the rods 39 and 40 suspended above thecathode and the current is supplied by means of the contacts 41 and 42.The supply cables may be directly connected to these contacts so thatsliding contact members and easily breakable fiexible connections areentirely avoided. If the positive pole of the source of current isconnected to the contact 41 and the negative pole to the contact 42 thespindle or pivot pin 27 and the rod 40 must consist of an insulator. Itwill be understood, however, that the insulation between cathode andanode can also be effected in any other well known manner so that shuntsto the rods 23 and 24 are avoided as far as possible. 1

My improved equipment is particularly suitable for producing layers orcoatings of such metals which require a high current density or voltagefor their deposition and in .which even a short interruption of thegalvanic decomposition of the electrolyte has an adverse effect upon thequality of the deposited metal coating or layer. Such metals are inparticular chrome, iron and cobalt, but even'with nickel and zincsimilar difficulties arise.

The treatment in the improved apparatus is particularly suitable forobjects or articles capable of rolling or tumbling, such as screws,balls, pins, rings and the like.

The objects should preferably be placed on the erforated shakin oroscillating tray in suc numbers that t 'ey form a single layer only andthe tumbling of articles over one another is avoided.

5 The perforations in the plate or bottom of the tray or trough must beprovided in such numbers and be of such sizes that the objects cannot bearrested for any length of time as otherwise the galvanic depositionwould be interrupted at the place of contact between the plate, tray ortrough and the object or article.

It will be readily understood that structural modifications may be madewithout departing from the spirit of my invention or he scope of theappended claims.

I claim as my invention:

1. In an apparatus for electroplating articles in bulk, a containerhaving an extended substantially flat bottom and means for connectingarticles resting on the bottom thereof cathodically to a source ofcurrent, an anode, means for supporting said tray-like containerin aninclined position and for periodically reversing the direction ofinclination,

and means for agitating the tray-like container while in positions ofinclination, whereby the said articles are caused to move intermittentlydown the inclined bottom first in one direction and then in the other.

2. Apparatus according to claim 1 wherein said means I for supportingsaid container comprises a crank, a connection between said crank andcontainer, and means for intermittently operating said crank.

3. Apparatus according to claim 1 wherein. said agitating meanscomprises an arm connected to said container and a rotary crankconnected to said arm.

4o 4. In an apparatus for electroplating articles in bulk, a containerhaving an extended substantially flat bottom and means for connectingarticles resting on the bottom thereof cathodically to a source ofcurrent, an anode,

means for oscillating said container in a substantially level position,and means for producing sudden impacts upon said container onoscillations in opposite directions whereby to agitate said articles andprotect them along the container in the direction in which the containeris moving when arrested.

5. Apparatus according to claim 4 wherein said means for oscillatingsaid container comprising a driving part and a yielding connectionbetween said driving part and container, whereby said container onimpact,

' can move independently of said driving means.

f3. Apparatus according to claim 4 wherein said means for oscillatingsaid container comprises swinging arms connected at opposite points tosaid container.

In testimony whereof I aflix my signature.

MARTIN KIRCHNER.

